Case-shift mechanism



J. A. HAGERSTROM.

CASE SHIFT MECHAMSM.

APPLICATION FILED AUG.31. 1911.

Patented May 20, 1919.

INVENTOR A ATTORNEYS I UNITED STATES PATENT onnro JOHN A. HAGERSTROMI, OF SCRANTON, PE WRITER COMPANY, OF SCRANTON, P

YORK.

. CASE-SHIFT MECHANISM.

Specification of Letters Patent. Patented lVIay 20, 1919.

Application filed August 31, 1917. Serial No. 189,107.

To all wkomz't may concern:

Be it known that I, JOHN A. HAGERSTROM, a citizen of the United States, and resident of Scranton, in the county of Lackawanna and State of Pennsylvania, have invented certain new and useful Improvements in Case-Shift Mechanism, of which the following is a specification.

This invention relates to typewriters and has for its object t9 provide means of improved construction for locking the case shift mechanism against accidental displacement while at the same time rendering said case shift mechanism instantly responsive when properly operated by the regular case shift lever. Further and more specific objects of invention will appear in the specification and be pointed out in the appended claims, reference being had to the accompanying drawings which exemplify my invention in its preferred embodiment.

In the drawings,

Figure 1 is a side elevation of my improved case shift mechanism, parts being broken away and parts shown in section;

Fig. 2 is a front elevation of the same. parts being broken away and parts shown in section;

Fig. 3 is a fragmentary side elevation similar to Fig. 1 with the parts in changed position.

In the preferred embodiment of my invention shown on the drawings, the case shift key' lever 1 is pivoted at 2, being normally retained in elevated position by means of a spring 3 which connects said lever with a bracket 4. A link 5 is pivotally connected at one end at 6 to the lever 1, the other end of said link being pivotally connected at 7 with one arm 8- of a lever which oscillates on its trunnion 9, the other arm 10 of said lever being provided with an enlargement 11 which slidably engages a lateral projection 12 on a bent lever 13 which oscillates about an axis 14. Said lever 13 is provided with a forwardly presented rail 15 which is adapted to receive suitable guides carried by the carriage (not shown on the drawings). Pivotally mounted in suitable brackets 16 is an oscillatory rod or bar 17 to which is connected one end of a torsional spring 18, the other end of said spring being connected to the bracket 16. Said spring is thereby adapted to impart a pressure which tends to move the rod 17 in an anticlockwise direction according to Fig. 1. Rigid with the rod or bar 17 is a radial plate or arm 19 which is adapted to be slidably engaged by thecurved arm 20 which preferably forms an integral part of the lever arm 10. WVhen actuated, said lever arm 10 is therefore adapted to displace the arm 19 forwardly as shown in Fig. 3. Mounted on the end of the rod 17 is a plate latch 21 provided with a socket 22 at its rear end which is adapted to fit down over a pin 23 which projects laterally from the lever arm 10, these parts forming an interlocking connection which prevents an accidental displacement of the case shifting mechanism when the key lever 1 is not operated. lVhen, however, said key lever is operated, the upward movement of the lever arm 10 by means of the arm 20, displaces the radial arm 19 in the position shown in Fig. 3, and thus releases the case shift look while at the same time, the enlargement 11 by slidably engaging the lateral projection 12 on the lever 13, lifts the rail 15 and thus imparts the case shift movement to the carriage.

I claim:

1. In a typewriter, an oscillatable lever adapted to impart the case-shift movements to a typewriter carriage, a second lever oscillatably engaging the first lever, a movable arm adapted to lock the first mentioned lever against movement, means interengaglng be tween said arm and the second mentioned lever for releasing the first mentioned lever,

second mentioned lever.

2. In a typewriter, an oscillatable lever adapted to impart the case-shift movements to a typewriter carriage, a second lever oscillata'bly engaging the first lever, a movable arm adapted to lock the first mentioned lever against movement, means interengaging betweerbsaid arm and the second mentioned lever for releasing the first mentioned lever, and a case-shift key lever connected to the second mentioned lever, said interengaging means comprising slidably engaging portions of said arm and second lever.

3. In a typewriter, an oscillatable lever for imparting the case-shift movements to a typewriter carriage, said lever being provided with a lateral extension, a second lever pivotally mounted and slidably engaging said lateral extension, a pivotally mounted arm for locking the first mentioned and a case-shift key lever connected to thelever against movement, means carried by the second mentioned lever for moving said arm to release the first mentioned lever, and a case-shift key lever operatably connected to the second mentioned lever.

4. In a typewriter, an oscillatable lever for imparting the case-shift movements to a typewriter carriage, said lever being provided with a lateral extension, a second lever pivotally mounted and slidably engaging said lateral extension, a pivotally mounted arm for looking the first mentioned lever eo rpm against movement, means carried by the second mentioned lever for moving said arm to release the first mentioned lever, and a case-shift key lever operatably connected to the second mentioned lever, said arm provided with yieldable means. for pressing it into locking engagement With the first mentioned lever.

JOHN A. HAGERSTROM. Witnesses;

MARY C. ROCHE, RUDOLPH MORSTADT. 

